ENERGY BALANCE ASSESSMENT CORE ? ABSTRACT The Energy Balance Assessment Core (EBAC) has been an integral component of the University of Colorado NORC since 1997. The EBAC provides support for the measurement of components of energy balance (e.g., energy expenditure and intake) and for assessing consequences of alterations in energy balance (e.g., body composition, substrate oxidation). The Overarching Aim of the EBAC is to provide expertise and support for obesity- and nutrition-related basic, clinical, translational, and transdisciplinary research for NORC investigators at CU-AMC and its affiliates. Services of the EBAC have been and will continue to be essential for many NORC investigators. Over the past 5 years, the EBAC supported a total 113 research protocols from 66 principal investigators; 52 protocols were active at the time the competing renewal application was prepared. The consolidation of the instruments and techniques used by multiple investigators in the EBAC enhances a) cost effectiveness, by reducing the need to duplicate expensive instrumentation and specialized staffing, b) safety for both staff and research participants, by overseeing the training required to safely operate instruments and conduct procedures, and c) data quality, by conducting regular maintenance and standardized calibration and quality assurance procedures. Specific Aims of the EBAC that will be ongoing over the next period of award are to: 1) provide consultation on experimental design, procedures, and data interpretation for NORC-related research and access to and assistance with the use of state-of-the-art instrumentation and approaches for measuring various aspects of energy balance; 2) oversee the maintenance, calibration, quality assurance, and scheduling of instrumentation and the training of personnel who utilize the instrumentation; 3) leverage resources and coordinate activities with other institutional programs that provide services that support energy balance research; and 4) expand services based on the needs of NORC investigators. In addition, the following Specific Aims will be completed during the next award period: 5) implement a new Core Facility Management System (iLab Solutions; Chicago, IL) that will improve the efficiency of core management and simplify access for investigators; and 6) develop a Resource Manual for the Objective Measurement of Physical Activity, which will include descriptions of technologies (e.g., accelerometry) and advantages and disadvantages of each. Since 1997, the EBAC has enhanced nutrition- and obesity-related research by overseeing the measurement of components of energy balance and body composition with a degree of accuracy and quality control that would have been difficult and more expensive for individual investigators to achieve on their own.